Film cassette including battery power supply



United States Patent Inventor Irving Erlichman Wayland, MassachusettsAppl. No. 766,548

Filed Oct. 10, 1968 Patented Dec. 1, 1970 Assignee Polaroid CorporationCambridge, Massachusetts a corporation of Delaware FILM CASSETTEINCLUDING BATTERY POWER SUPPLY 16 Claims, 4 Drawing Figs.

US. Cl 95/11, 206/62 Int. Cl. G03b 17/26 Field of Search 95/13, 19,

31(dec), 66; 96/76; 206/62(lnquired) [56] References Cited UNITED STATESPATENTS 2,989,906 7/1961 Rentschler 95/3 lX 3,447,437 6/1969 Tiffany95/13 Primary Examiner.lohn M. Horan Assistant Examiner-M. L. GellnerAttorneys-Brown and Mikulka, William D. Roberson and Gerald L. SmithABSTRACT: A film cassette for photographic cameras configured to retaina number of film units for sequential exposure and a fiat batteryassembly for powering camera instrumentalities until the film supply isexhausted. The structure inclufdes a spring loaded platform positionedbetween the battery assembly and film units for compressively retainingthe batteries and supporting the film units.

Patented Dec. 1 1970 Sheet 1 or:

I N VENTOR.

ATTORNEYS Patented Dec. 1970 Sheet m w m 2 on E. 3 n No 3 mm 8 2* mm-w\\\ v 7 vw M WNW 1 1 1| r Hym u M 3 ow h'llllrllllgl INVENTOR.

ATTORNEYS FILM CASSETTE INCLUDING BATTERY POWER SUPPLY The presentinvention relates to electrical power supply systems for photographiccameras, and more specifically, to a configuration for a discardablefilm retaining cassette which intimately incorporates a battery powersource.

BACKGROUND OF THE INVENTION In the course of improving the design ofphotographic systems, advantage has been recognized in providing for thereplenishment of a camera power supply concurrently with the renewal ofits film supply. By structurally uniting a battery power supply withfilm unit containers or cassettes, this replenishment is assured and theresultant union of components has been found to derive severalinterrelated functional improvements. The power source included withinthe film units is used only during the relatively limited operationalinterval determined by the number of exposures in a film cassette. As aconsequence, the battery formed in conjunction with each film cassettemay be of the primary variety. For the limited utilization occasioned bythis arrangement, such batteries will retain their most efficient chargecharacteristics and advantage may be taken of the available low cost ofprimary battery structures to the extent that they may be incorporatedwith disposable cassettes or film containers. Under current batterydesign capabilities, this discardable feature is available at costscomparable with conventional photographic battery power sources.

When the battery is'mounted within a disposable film cassette, it sharesthe environmental protection normally afforded packaged film.Consequently, until it is utilized within a camera as a power source,the battery will be stored under optimum energy conserving conditions.For instance, cassettes containing unexposed film are generallywarehoused at controlled lower temperatures and within sealedcontainers. Additionally, unexposed film storage procedures include moreor less rigidly administered dating techniques established incorrespondence with the relatively short shelf lives of the product. Thestorage requisites for primary batteries ideally correspond with theseconditions. Charge retention is maximized at lower storage temperatures.Chemical decomposition is minimized within a low temperature protectiveenvironment. Of particular advantage, the restricted storage periods forfilm fall in correspondence with the limited shelf life of the primarycells. As a consequence, the primary cells are made available for usewhile uniformly retaining a substantial portion of their original energycontent.

Cassette structures within which batteries are incorporated necessarilymust be the subject of careful design attention. The materials fromwhich cassettes are fabricated and their configurations should beselected not only in correspondence with the economic considerations ofdisposable systems but also in keeping with functional requirements forstrength, lighttight integrity and size. A practical union of thefunctions of battery mounting and photosensitive film retention suggeststhat the battery arrangement ideally should complement the filmpositioning apparatus of a cassette structure. However, the union mayresult in an overly involved structure where the cassettes areconfigured for use in cameras of the internally processing orself-developing variety. Film containers for these cameras function toretain aplurality of photosensitive film units which are internallymanipulated so as to be sequentially positioned at an exposure frame oraperture disposed within one surface of a cassette. Such film unitsgenerally incorporate rupturable pods containing developing materialsused by processing mechanisms positioned within a camera housing. Thesequential manipulation of each film unit through the cassette structureto a position for exposure, then out of the cassette and into theprocessing mechanism must be performed with considerable accuracy andreliability.

When battery power systems are introduced into these cassette assembliesfor self-processing cameras, design modifications to their shape andinternal configuration must be minimized. Additionally, in order tomaintain acceptably low production costs, the modified cassettestructures should be fabricable with efficient high volume productiontechniques.

SUMMARY OF THE INVENTION The present invention provides photographicapparatus including a film cassette assembly uniquely adapted to retaina select number of photosensitive film units in position for theirsequential exposure and also to efficiently carry a battery arrangementfor powering the instrumentation of a camera within which the cassetteis insertable. using batteries of flat configuration, the cassettestructure incorporates an internal mounting arrangement for flatbatteries while requiring no significant increase in size or alternationof a shape otherwise required for retaining the film units alone. As aconsequence, the cassette structure is available for use with moderncompact camera structures.

The inventive cassette is configured from a significantly small numberof structural components which are typified in having noncomplex and,therefore, economically fabricated shapes. As a distinguishing feature,these parts are designed to mutually cooperate in providing the dualfilm unit and battery retaining functions of the device.

The simplicity realized from imparting a dual function to components ofthe cassette permits its assembly with low cost, high volume procedures.By selecting the output ratings of the batteries mounted with thecassette structure in correspondence with the camera instrumentationpower demands required for exposing and/or processing only the filmunits contained within each assembly, the low cost cassettes arediscardable following the exhaustion of their film supplies.

The cassette assembly of the invention is particularly characterized inthe use internally of a film supporting platform member having outwardlybiased spring means. Oriented between a stacked array of film units anda flat battery assembly, the platform serves the dual function ofsupporting and sequentially elevating stacked planar film surfaces topositions for exposure at one face of a cassette while providing acompressive force against a cassette wall which is utilized by thebattery assembly. The compressive force or bias derived from the springloaded platform may be used to improve and simplify the terminalinterconnections of flat batteries positioned within the cassetteparallel with and opposite from the film units. Where flat primarybatteries are employed within the cassette structure, additionaladvantage is realized in that their. constituent primary cells mayperform more reliably when maintained under slight compressive loads.

An additional feature and object of theinvention is to provide acassette structure for use with cameras of the selfdeveloping varietywhich is configured to include a housing having a frontal surfacedefining an exposure frame opening behind which photosensitive filmunits are exposable in sequence. The film units are supported againstthe front surface frame by a resilient spring loaded platform which alsofunctions to compress a flat planar primary battery assembly which isinternally nested against a cassette back wall disposed oppositely fromits frontal surface. The platform is also used to retain across-connecting terminal strap or bus against selected inwardly exposedelectrode surfaces of the batteries. Terminal access means areassociated with the back wall of the cassette for purposes ofinterconnecting the power supply with power consuming instrumentation ofa photographic camera.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises, the apparatus possessing theconstruction combination of elements and arrangement of parts which areexemplified in the following detailed disclosure.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of acassette assembly embodying invention shown within a camera and withportions broken away to reveal internal structure;

FIG. 2 is a perspective view of a cassette assembly according to theinvention showing its major structural components in exploded fashion;

FIG. 3 is a sectional and fragmentary view of a cassette structureaccording to the invention portraying the interrelationship of a stackedfilm array, a supporting platform and flat battery power source; and

FIG. 4 is an enlarged sectional and fragmentary view of a primarybattery unit.

DETAILED DESCRIPTION OF THE DRAWINGS The cassette arrangement of theinvention is capable of incorporation within a wide variety ofphotographic camera structures. For purposes of illustration, it isdescribed in connection with a camera configuration which incorporatesan electrically powered internal film processing function. Thisself-processing function along with those providing exposure control andartificial subject illumination derive their supply of power solely fromthe batteries furnished with a disposable cassette.

Referring to FIG. 1, the camera structure shown generally at 10 isillustrated having a hexahedron configuration formed from fourarticulative housing portions or sections. These sections include a baseor principle body housing l2 to which is pivotally attached a forwardlens and mounting unit 14 and a top section 16. A hinge arrangement forthe latter pivotal connection is indicated at 17. Top section 16 andforward unit 14 are each hinged to the edges of a frontal section 18,thereby completing the peripheral structuring of the assembly. Thepivotal interconnection of frontal section 18 with its contiguouscomponents is provided by hinge assemblies, the center pins of which areshown at 20 and 22. Camera assembly 10 is of a folding variety,accordingly, the side panels of the camera body are formed of fan-likebellows members one of which is shown at 24. The bellows members andperipheral components cooperate to provide a lighttight internal chamberwithin which photosensitive film materials are exposed. To retain thesephotosensitive sheets in position for appropriate exposure, main bodyhousing 12 is configured having a receiving chamber for removablyretaining a film cassette 26. I

During a film exposing sequence, an exposure system including a lens,aperture and shutter arrangement mounted in forward unit 14 functions inthe usual manner to image a scene being photographed upon aphotosensitive film sheet positioned at the upper surface of cassette26. The optical path through which this is accomplished includesreflection from the inner, slanted surface of top section 16. Thisfolded optic arrangementpermits a smaller, more compact and convenientcamera housing design. A more detailed description of such compactcamera structures is provided in a copending I US. Pat. application ofLand et al. Ser. No. 655,850 filed July 25, I967 and assigned to theassignee of the instant application.

Looking to the general configuration of the cassette 26, it is seen tobe formed having a rear wall 28 the exterior surface of which nestsagainst the bottom panel 30 of main body housing 12. Depending from rearwall 28 are sidewalls as at 32 and 34. Spaced oppositely from rear wall28 is a forward wall 36 within which is formed an exposure frame opening38. Positioned beneath the forward wall 36 and its frame 38 is anassemblage of stacked film units depicted generally at 40. The term filmunit" is used herein to refer to any of the broad variety of film and/orsheet processing structures incorporated within a cassette. The filmunit depicted in the drawing are of the type shown and described in US.Pat. applications of Edwin H. Land, Ser. No. 622,287 and Edwin H. Landet al. Ser. No. 622,286 both filed Mar. 10, 1967. Each of the unitsincorporates all of the material necessary to produce a positivephotographic image. The general structure of each includes aphotosensitive material which is cooperatively combined with atransparent image receiving sheet, Each film unit also includes arupturable pod or container for holding a developing agent, a series ofwhich are illustrated in stacked relationship at 42. Beneath the filmsupply 40 there is positioned spring loaded platform 44 having a filmsupporting surface 45. The platform is formed of a resilient materialand incorporates a compressive spring support arrangement formedintegrally from depending tab members 46, 48 and 50. The

resilient platform functions to urge the forwardmost film unit intoposition against frame 38 at the imaging plane for appropriate exposurewithin the internal chamber of the camera.

Following the exposure of a film unit at the image plane, means areprovided within the camera for engaging this forwardmost film unit anddrawing it from the cassette 26 through an exit slot 52 for introductionto a pressure applying roller assembly as shown at 54. Assembly 54 isportrayed as a pair of cooperatively rotating motor driven rolls 56 and58. As a film unit is advanced through the pressure applying assembly 54its attached pod is ruptured, processing liquid within the pod is spreadbetween its respective film components and an image developing functioncommences.

To supply electrical power for the pressure applying assembly as at 54,as well as to power the exposure instrumentation of the camera, a flatbattery assembly is included within the cassette structure 26. Thisbattery assembly is shown to include two flat units 60 and 62 which nestin indentations formed within cassette rear wall 28. Over the batteriesis positioned a metallic plate or strap 64. Plate 64 is urged againstthe batteries 60 and 62 by virtue of the pressure imposed by resilientplatform tabs 46, 48 and 50. The plate, while functioning tocompressively retain the battery structure in appropriate nestedposition, also may serve as an interior terminal connecter for thebattery assembly.

The electrical power supply provided by flat battery units 60 and 62 isdistributed into the power consuming instrumentation of the camera byterminal interconnections made through openings as at 66 and 68 whichare positioned in the rear wall 28 of the cassette. Connection betweenthe circuitry of the camera and the battery electrodes is effected byspring loaded terminals as at 70 and 72 which are permanently mountedupon bottom panel 30 of main body housing 12. Terminals 70 and 72 areconnected respectively with conductive straps 74 and 76 which aremounted in insulated fashion within the bottom panel 30 and areelectrically tied in with the instrumentation of the camera throughadditional connection not shown.

In the assembly thus far described, the film supporting platformarrangement 44 may be seen to provide a dual operational function. FOrinstance, the platform continually positions the foremost film unitbefore the exposure aperture 38, Le, at the image plane of the camera.Additionally, the platform, through its resilient depending tabs 46, 48and 50 compressively acts against the assembly of fiat batteries 60 and62. The conductive plate 64, which may be interposed between theresilient platform and the battery assembly, uniformly distributes thecompressive force of the spring loaded platform while providing forbattery electrode interconnection.

The cassette arrangement of the invention is configured so as to bediscardable upon exhaustion of its film supply. In keeping with thisdiscardable feature, the battery power unit incorporated with thecassette is selected having a power capacity sufficient to operatecamera exposure and processing instrumentation for a select number offilm exposures. To maintain necessary low production costs, however, thebattery units must be mountable within the cassette structure using onlya minimum number of parts and with simplified and practical productiontechniques. This necessary simplicity and practicality is provided withthe present cassette structure as portrayed in the explodedrepresentation of the power unit portion of the cassette at FIG. 2.Looking to the FIG., it may be seen that the flat battery panels 60 and62 are dimensioned so as to be readily insertable within indentations inthe rear wall of the cassette shown respectively at 78 and 80. Tofacilitate their mounting, a small amount of glue may be used to holdthem in position. Terminal connection between battery panels 60 and 62is provided by the simple expedient of positioning plate 64 over theiroutwardly exposed surfaces. To assure proper contact of plate 64 uponthe electrode surfaces of the battery panels the spring loaded featureof platform 44 is used. To provide external access to the terminals ofthe battery structure, holes as at 66 and 68 are formed within the rearwall of the cassette. By simply placing a cassette within the camera,terminal interconnection between the battery units and camerainstrumentation is assured. Since the holes 68 and 70 are entirelycovered by one surface of the battery units 60 and 62, the lighttightintegrity of the rear wall of the cassette is maintained. As may beevidenced from the foregoing, the assembly procedure for placing thepower unit within the cassette involves highly practical sequentialassembly techniques. The components forming the power unit assembly arefew in number and of a modular nature. Consequently, they are availableat costs sympathetic with the discardable feature desired in thecassette arrangement.

Primary batteries, generally considered those which cannot be recharged,have the power capacities and low unit costs needed for incorporationwithin the cassette. Referring to FIG. 3, a flat primary batteryassembly is shown mounted upon the rear wall of a cassette structure.Two battery units 60 and 62 are used within the power arrangement andeach of the 'units is formed of two discrete primary cells which aresuperimposed for series connection within a cassette. Battery units 60and 62 are mounted upon wall 28 in reversed orientation and areelectrically united in series by pressure plate 64. This arrangementprovides a series connected output at the terminal openings 66 and 68.In addition to providing a series interconnection of the battery units60 and 62,, plate 64 maintains the cell structures of the units under aminor compressive load. It has been empirically determined that suchcompressive loading aids in minimizing corrosive breakdown of the cellsby enhancing the integrity of the laminar structure from which they areformed. The battery units are pictured in exaggerated scale to revealthis laminar structure. To prevent leakage, portions of their externalsurfaces are coated with a plastic or the like as depicted at 82'and 84.

The structure of one of the battery units as at 60 is more clearlyrevealed in an enlarged scale fragmentary view at FIG. 4. Referring tothat FIG., the dual cell structure 60 is revealed as a multilayeredarrangement of cells configured in series fashion; The materials fromwhich each of the cells is produced may vary to meet specific designneeds, however, conventional low cost carbon-zinc primary batterycomponents will be found suitable for most applications. Two superposedcells 60,, and 60,, are shown in the FIG. The upper cell 60a isfashioned having a cathode electrode formed of a thin layer of carbon Cover which has been deposited a thin aluminum film A,. Aluminum film Afunctions to provide a conductive path and terminal from which theelectrode may be tapped. An anode electrode Z, for the first cell isdepicted as a thin sheet of zinc. Between this anode Z and cathode C, isan electrolytic paste E, and paper separator P,.

A second and identically structured cell 60 is shown laminated with cell60a Fabricated in fashion similar to cell 60,,, cell 60,, is shownhaving a cathode layer C of carbon over which is deposited an aluminumfilm A A layer of electrolytic paste E and paper separator P separatethe cathode layer C from an anode Z fashioned of zinc.

The capacity of each of the primary battery cells as described will varysubstantially in proportion to the areas of their flat or activesurfaces. Typically, one such cell will produce about 0.10 to 0.15amperes per square inch of surface area while yielding about 1.5 volts.For popular photographic camera sizes, an area within each film cassetteavailable for retaining the batteries will provide about l0 to 12 squareinches of practical surface. It follows, therefore, that the batterycapacity desired for a film supply-power source combination readily maybe varied through the simple expedient of combining a select number ofdiscrete cells of predetermined dimension.

The intimate association of a flat multicell primary battery with a filmretaining cassette holds particular advantage as a result of the filmpackaging techniques common in the industry. Each loaded film cassetteis hermetically sealed within lighttight moistureproof containers.Further, the film is conventionally stored at controlled lowertemperatures for limited periods of time until released for purchase bythe consuming public. The combination of protection from an externalinfluence by packaging along with storage for limited periods underideal temperature conditions greatly enhances the reliability of thepower source provided by the batteries. In the same light, the primarybatteries will be utilized within the relatively short period of timerequired to exhaust the nominal number of exposures available from thefilm supply of the eassette structure. The reliability of the cells isadditionally enhanced by the film supporting and battery compressingfunction of the internal structure of the cassette. All of the abovefactors combine to permit the use of the inexpensive flat cellconfiguration of a primary battery.

Since certain changes may be made in the above system and apparatuswithout departing from the scope of the invention herein involved, it isintended that all matter contained in the above description or shown inthe accompanying drawings shall be interpreted as illustrative and notin a limiting sense.

I claim:

1. A film cassette for photographic apparatus comprising in combination:

a plurality of photographic film units, each including at least onephotosensitive layer, stacked in parallel relationship;

a cassette body having mutually spaced rear and forward walls, saidforward wall including a frame opening through which said film units canbe sequentially exposed;

at least one planar electrochemical battery positioned over an inwardsurface of said rear wall;

spring loaded platform means disposed within said cassette bodyintermediate said film units and said battery for supportively urgingsaid film units into position for exposure at said frame opening andsimultaneously compressively biasing said battery against said rearwall; and

means exposing terminals of said battery for power supplyinterconnection with photographic apparatus within which said cassetteis insertable. 2. The film cassette of claim 1 wherein: at least twosaid planar electrochemical batteries are positioned over an inwardsurface of said rear wall; and

including an electrically conductive planar support member interposedbetween said flat platform means and said batteries and forming aterminal interconnection between said batteries.

3. The film cassette of claim 1 in which:

said planar battery is configured having a plurality of discrete seriesconnected electrochemical primary cells formed with paired planarelectrodes; and

said terminal exposing means includes at least one opening formed withinsaid cassette body rear wall in a position selected for exposing atleast a portion of one said electrode. 4. The film cassette of claim 1wherein: at least two said planar batteries are positioned over aninward surface ofsaid rear wall in a manner providing a mutuallyreversed orientation of their polarities; and

including an electrically conductive planar support member interposedbetween said platform means and said batteries and forming a terminalcoupling between said batteries.

5. The film cassette of claim 4 in which:

each said planar battery is formed of at least one electrochemicalprimary cell having paired planar electrodes; and

said terminal exposing means includes at least two openings formedwithin said cassette body rear wall and selectively spaced to expose atleasta portion of outwardly facing cell electrodes of oppositepolarities.

6. The film cassette of claim 1 in which said planar battery is aprimary battery.

7. The film cassette of claim 6 including a planar support memberinterposed between said platform means and said battery.

8. The film cassette of claim 7 in which said spring loaded platformmeans is configured as a sheet of resilient material having integrallydepending tab means extending therefrom for resiliently supporting saidplatform against said planar support member.

9. The film cassette of claim 8 wherein said tab means compriseprotuberances integrally connected with and formed from said platformmaterial and biased outwardly therefrom to provide a predeterminedoutwardly biased spring force.

10. Apparatus for exposing photographic film units each including atleast one photosensitive layer comprising:

a photographic camera including: electrically powered means within saidcamera for performing at least one operation in connection with theexposure of said photosensitive film units; a housing having a receivingchamber for retaining a quantity of said film in position for the saidexposure; electrical contact means disposed within said chamber forreleasably connecting said electrically powered means with a batterypower supply; a disposable cassette including:

a plurality of said film units stacked in parallel relationp; a cassettebody configured for removable insertion within said receiving chamberand having mutually spaced rear and forward walls, said forward wallincluding a frame opening through which said film units can besequentially exposed; at least one planar electrochemical batterypositioned over an inward surface of said rear wall and having an energycapacity sufficient to operate said electrically powered meansthroughout the exposure of said select number of film units; springloaded platform means disposed within said cas sette body intermediatesaid film units and said battery for supportively urging said film unitsinto position at said frame opening and simultaneously compressivelybiasing said battery against said rear wall; and means exposingterminals of said battery for power supply interconnection with saidelectrical contact means. 11. The apparatus of claim 10 in which: saidplanar battery is a primary battery; and said cassette includes asupport member interposed between said platform means and said battery.12. The apparatus ofclaim 11 in which: said spring loaded platform meansis configured as a sheet of resilient material having integrallydepending tab means extending therefrom for resiliently supporting saidplatform against said planar support member. 13. The apparatus of claim10 wherein: at least two said planar electrochemical batteries arepositioned over an inward surface of said cassette rear wall; andincluding an electrically conductive planar support member interposedbetween said platform means and said batteries and forming a terminalinterconnection between said batteries. 14. The apparatus of claim 10wherein: said planar battery is configured having a plurality ofdiscrete series connected electrochemical primary cells formed withpaired planar electrodes; and

said terminal exposing means includes at least one opening formed withinsaidcassette body rear wall in a position selected for exposing at leasta portion of one said electrode.

15. The apparatus of claim 10 wherein:

at least two said planar batteries are positioned over an inward surfaceof said rear wall in a manner providing a mutually reversed orientationof their polarities; and

including an electrically conductive planar support member interposedbetween said platform means and said batteries and forming a terminalcoupling between said batteries.

16. The apparatus of claim 10 wherein:

each said planar battery is formed of at least one electrochemicalprimary cell having paired planar electrodes; and

said terminal exposing means includes at least two openings formedwithin said cassette body rear wall and selectively spaced to expose atleast a portion of outwardly facing cell electrodes of oppositepolarities.

